Heat a heavy skillet. Add the olive oil. Add the chicken thighs and brown on both sides over medium high heat. Be sure to sprinkle one side lightly with salt and pepper. Add the onions and cook for a few minutes. Add the slices of mushrooms and season with salt and pepper. Be sure not to over salt and pepper. Cover and lower heat to medium low. Cook for approximately 20 minutes or until mushrooms have wilted down and chicken is cooked thoroughly. Add the wine and boil liquids in pan for a few minutes more.